Crystal structure of a protein involved in cell division and cell wall biosynthesis from Mycoplasma pneumoniae, a bacterium known to cause pneumonia.

Mycoplasma pneumoniae is a very small bacterium, in the class mollicutes. This class of organisms lack a peptidoglycan cell wall present on all other firmicute bacteria. Instead, it has a three layer cell membrane which incorporates cholesterol compounds, similar to eukaryotic cells. Lacking a cell wall, these organisms are resistant to the effects of penicillins and other beta-lactam antibiotics, which act by disrupting the bacterial cell wall- Scytek Labortories Inc